Leakage indicator and connections.



E. B. WEDMORE.

LEAKAGB INDICATOR AND CONNECTIONS.A APPLICATION FILEAD MAB. 8, 1911.

1,085,309, Patented Jan. 27, 1914 [NVENTUH FDMUND .E I/VEDMUH E',

H35 TTUHNEY.

. UNITED sTATEs PATENT oEEIoE.

EDMUND WEDMOBE0F RGBY, ENGLAND, ASSIGNOR T0 GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

Lumen INpIcATon 'AND coNNEcTroNs.

To all um/n, it may concern Be it :known that I, EDMUND B. `WEnV Mona, a subject of the King of Great Britain, residing at Rugby, England, have invented. certain new and useful Improvementspin Leakage Indicators and Connections', of which the following is a specification.

My invention-relates to a relay or indicator andwiits connect-ions in a system of distribution. 1 I

Itis common to use a relay or indicator y rent and hence-exert amore r less pull,

therebywunbalancing the beam and indicating the trouble. These devices operate in proportionpto the difference between the pulls'. on-the different parts of the beam, ,which 4differencev is a function of the difference' betweeny the ampere-turns' on the' various coils. l-Now,- as is well known, the permeability varies with the flux density, though not directly. In order to make the ,devicegas sensitive `as possible, it is neceslsary that the permeability be large, and the device small. 0n 'any distribution system; the device must have a large number of series turns inl order to operate on a small value otlakage current toy ground which causesha @greatnumber of ampere turns for the normal series current, 'and hence with a smalLde'vicea greilt'tlux 'density and small pcr'nieabilty due to :saturation of the iron ,coi-@WA large device is thereforenecessary VI"to secure a. ylarge value for permeability. 'l`o'overcome`ithis undesirable feature I employv another vcoil acting in opposition to eachl s`eriescoil."and therefore tending to hringthe flux density of ea'ch armature to.

a more desirable value; `this second coil may be energizedinlvarlous ways to secure the desired" result and I have shown here the connecting of the auxiliarycoils in series across the line.

In the drawings which form a part of this specification" similar reference characters- 'referto the .same parts.

Figure 1` is a" diagrammatic view of a part of a system of distribution showing the connection of my. protective device in the spcmauon of Letters Patent.

:Application led Inl-ch 8, 1911. Serial'No. 613,143.

Patented Jan. 27, 1914.

system. Fig. 2 is an elevation partly in section of one form of the device.

I have shown my protective 'device as a relay which may close a circuit 'to another device at any place which will there indicate that trouble has occurred, or may close a circuit to operate a circuit breaker to open -the main system. It is obvious that the device illustrated inay be used to itself indicate that trouble has occurred and notact as a. relay at all; as applied to a two wire direct current cirbuit, but its use is of course not limited to such a system. The relay I have shown has I have shown 'my device.`

a lever 1 pivoted at 2. At bequal distances from the pivot 2are armatures 3, each of which is controlled by a solenoid. Each solenoid has two coils 4 and 5 of an appropriate-number of turns. lever I have shown the contacts 6 which, when trouble has occurred, contact with eitherpor both of the contacts 7, which may be mercury cupspas shown or any other common form of contact. Of course, when the device 1s to be used as an indicator directly At the ends of the and merely, itI is not necessary that these contacts be used. The pivot 2 is supported by a longitudinally movable member 8 which operates in'th'e guide 9, and is supported in turn bythe spring 10. At the bottom of the guide 9 by being moved into or from the guide 9 may increase or decrease the tension on ythe spring 10 and thusedetermine at what overload the device will operate; this overload operation will be later described. Although I have described this specific form of relay and indicator, it will be understood tht this specific form is not necessary, but thatthis is inserted the screw 11 which specific -form is shown as one which includes the necessary features of my device.

One coil of each pair is connected in series I with a main of the distribution system.

The other coils are to be supplied with en-` ergy in such quantities that their pull on the armatures 3 will be equal and balance each other, and they are preferablyuwound so that for the average load on the system they will neutralize the effect ofthe series coils. In Fig. 1 I have shown the coils 4 connected in series with the mains 12. To

supply the coils 5, which as connected should have the Same number of turns, I have con. nected them in series between the mainsy12. In order that one of the series coils may take an' increase of current on the grounding The operation is as follows: When a,

ground occurs, for instance, on one main as at 14, the lower series coil will carry more current than the other. Under normal conditions the two coils 5 exactly balance each other and the coils 4 exactly balance each other and hence the lever l stands in the mid-position as illustrated in Fig. 2. Dur- 111g the continuation of the ground at 14, since one series coil has more current iiowing through it than isiiowing through the other, the lever l is unbalanced, and that end of the lever which is controlled by the first coil is pulled down. Although there is a Ground at 14, nevertheless it will be apparent Irom the drawing that the coils still balance each other. Suppose for another' example that instead of there 4being a ground the two mains 12 are short circuited at some point. The coils 4.- although taking a much greater current than under normal condi tions still balance each other, the coils 5 still balance each other and neither end of the lever 1 experiences a greater pull than the other, but it the combined pull ot' the two is greater than the pressure exerted by the spring 10 the lever 1 is bodily moved laterally downward, thus indicating the short circuit. The screw 11 thus becomes of use to regulate the amount of overload allowable. Although I have shown this specific form of relay and shown it connected in this speciiic system, of distribution, it will be understood of course that my invention is not limited to exactly what is shown but that. the scope of my invention is deiined in the appended claims.

What I claim as new and desire to secure by Letters Patent of the United States, is-

1. In a system of distribution, mains and a relay or indicator, said relay or indicator including a movable member, a single solenoid connected to receive current proportional to the current in each main and controlling said member, and an opposing coil adjacent each solenoid.

2. In a system of distribution, mains and a relay or indicator, said relay or indicator including a movable member, a solenoid "connected to each main and opposing the action on the movable member of each of the remainder of the solenoids, and a constantly opposing coil adjacent each solenoid.

S. In a system of distribution, mains and a relay or indicator, said relay or indicator including a movable member, a solenoid in series with the load in each of the mains and acting on the movable member and constantly opposing coils adjacent the solenoids and connected in shunt to the load.

4. In a system of distribution, mains and a relay or indicator, said relay or indicator including a movable member, a. solenoid for cach main connected to receive current pro- -portional to the current therein and acting on the movable member, and opposing coils adjacent the solenoids and connected in shunt to the load.

5. In a system of distribution, mains and a relay or indicator, said relay or indicator including solenoids connected to the mains, a beam responsive to the unbalanced action ot' the solenoids, a ulcrum for the beam, and a yielding means for the fulcrum.

6. In a system of distribution, mains and a relay or indicator, said relay or indicator including solenoids connected to the mains, a beam responsive to the unbalanced action of the solenoids, a fulcrum for the beam, and an adjustable yielding means for the -lulcruml 7. An indicator including a balanced beam, solenoids controlling said beam at diierent sides of the fulcrum and yielding means supporting said beam.

8. A relay including a balanced beam, coils controlling said beam at different sides of the fulcrum, contacts on said beam, contacts to be engaged by said contacts on the beam and yielding means supporting the beam.

9. An indicator including a balanced beam, solenoids controlling said beam at diilerent sides ot' the fulcrum, yielding means supporting said beam and means for adjusting the tension of said yielding means.

In witness whereof, I hereunto set my hand this 20th day of February, 1911i.

EDMUND B. VVEDMORE.

Witnesses I". I. BRADLEY,

ERNEST M. WARD.

Copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. C. 

